Such an apparatus for closing filled envelopes may be integrated in an insertion machine, or else it may merely be coupled to the outlet from an insertion machine. In the insertion machine, envelopes are presented opened to a filling station which also receives folded documents for insertion into the envelopes. After they have been filled, the envelopes are evacuated from the filling station while still open. The apparatus which closes them may be used in turn for directly feeding a "franking" or postage machine, or it may deliver them to a storage magazine.
In conventional manner, apparatuses for closing envelopes receive the envelopes which are presented thereto separately from one another and with their flaps open. The apparatuses moisten the gum on the flaps, and then fold the flaps towards the corresponding envelope bodies in order to close the envelopes. French certificate of utility number 219532 describes such prior art apparatus.
In the embodiment described in that document, the envelopes to be closed are received on a platform, with the envelope bodies resting on and driven by the platform, while their flaps project beyond the platform and hang down freely. While each envelope is being displaced on the platform, a deflector guides the flap between a moistening member and an associated backing pressure member, both mounted beneath the platform. This moistening member is a wick dipping in a supply of water. The backing pressure member folds and firmly presses the gummed region of the flap against the wick in order to moisten the gummed region by wiping it over the wick.
This backing pressure member extends beyond the moistening member or is associated with another deflector in order to continue folding the flap and to guide it through an opening provided in the platform. Beyond this opening, a backing pressure plate seals the flap against the body of the envelope.
These parts for suitably guiding the flap and pressing its gummed region firmly against the wick are complex in shape, and they are inconvenient and expensive to make. In addition, they give rise to an apparatus for closing envelopes which is relatively voluminous.
The object of the present invention is to provide apparatus for closing envelopes which avoids the above drawbacks and which operates reliably.